Offroad-Express

KZJ78 manual with methanol injection and electronic fuel cut bypass.

Previously, I could cruise up the same hill at 100kmph on 5th gear, EGT peaks at around 700 but I'm already on top of the hill.
Foot isn't flat on the accelerator.

Recently on the same hill at 5th gear, truck could barely go beyond 80kmph. EGT peaks at 615.Change down a gear and could barely go more than 85kmph. EGT still at 615 on 4th gear.
Foot is flat on the accelerator.

Same conditions but something must have gone wrong. Not quite sure what's wrong as I'm still quite new to all this.

It feels like the truck's power reverted back to before the mods were done.

Any ideas?

Talk to the boys who did the meth injection.... Have you done anything recently on the truck?

Maybe blocked fuel filter ?, sounds like not enough fuel getting through
Cheers
Tim

Yeah it does feel like not enough fuel is getting through. Methanol injection still working fine. The methanol is still being used up.

Nothing done recently that could affect the engine.

Also did a round trip from Akl to Palmy. On the way there, everything was working right. While I'm there I had a workshop did some changes on the exhaust so it's not hitting the fuel tank and chassis. They also extended the diff breather lines and changed brake hoses. On the way back I felt that something was different.

Other than the fuel filter, anything else that I should look at?

Hmmmmmm you need to look at the fuel lines... maybe one has been kinked when they were mucking around with exhaust. As said you had some work done and now its different. They may have knocked something... Hope fully the brakes aren't dragging....

Just wondering if this is possible?

If there's something wrong with the fuel lines or fuel filter, means less fuel going in to the combustion chambers, also means less exhaust air coming out, hence turbo doesn't spool up as hard?

Because the first thing I noticed was the turbo seems quieter than usual at 100kmph. I thought my mind was playing games with me until I really noticed something wrong when going up that hill.

i agree with the above. start with fuel filter, check the fuel lines. check no fuel connections are loose (sucking in air) and are on the right pipes (could have been undone and put back on the wrong pipes).

How is the fuel cut and meth injection controlled? If you have an electronic controller that is programmable could it have been reset by disconnecting the battery when the welding was done?

Dan, do they normally disconnect batteries for welding? I'm no expert in it but why do they do that?

I'm not even sure how they work and where they are. Will ring Kaiapoi Repowers on Monday to ask them where the electronic boost cut controller is at. Anyone else had something similar done?

I opened up the glove box compartment and the nothing near the ECU looks new. Maybe they reprogrammed the ECU?

Batteries are disconnected or a surge protector put on across the battery terminals to prevent electrical spikes from mig welder.

1 thing to check, is it actually getting full throttle travel?

crazydragon wrote:KZJ78 manual with methanol injection and electronic fuel cut bypass.

Previously, I could cruise up the same hill at 100kmph on 5th gear, EGT peaks at around 700 but I'm already on top of the hill.
Foot isn't flat on the accelerator.

Recently on the same hill at 5th gear, truck could barely go beyond 80kmph. EGT peaks at 615.Change down a gear and could barely go more than 85kmph. EGT still at 615 on 4th gear.
Foot is flat on the accelerator.

Same conditions but something must have gone wrong. Not quite sure what's wrong as I'm still quite new to all this.

It feels like the truck's power reverted back to before the mods were done.

Any ideas?

How about checking the air filter and hoses. If blocked or a collapsing hose will affect overall power as well.